Clamp



Aug. 1,1967 E BQDEN ETAL 3,334,197'

CLAMP Filed April 50, 1964 nited States gPatent CLAMP Donald Eric Boden, Sale, and .lames Bruce Robertson, Altrincham, England, assignors, by mesne assignments, to The Rucker Manufacturing Company, Oakland, Calif., a corporation of California Filed Apr. 30, 1964, Ser. No. 363,739 Y Claims priority, application Great Britain, May 16, 1963,

19,590/ 63 6 Claims. (Cl. 191-40) This invention relates to clamps, and more p-articularly to clamps designed to hold conductors in spaced apart relation to a support member such as a frame or wall.

In overhead electrication systems such as those used to provide current for portable cranes, hoists and the like, a plurality of conductor bars are supported in closely spaced relation to provide power for the electrical equipment which is moved on gui-de rails adjacent the conductor bars. Conventionally, such overhead electrication systems utilize steel clamps to support insulated conductor bars in closely spaced relation and a plurality of movable collector shoes cooperate with the conductor bars to transfer power to the portable equipment.

While it is desirable to connect such metal clamps to ground in case the system breaks down and the bare conductor bars contact the clamps, it is also important for normal operations to provide simple means for insulating the conductor bars from the frame to which the conductor clamps are attached.

In many applications, the conductor bars are formed of spaced apart, heavy conductive rods or wire having a connecting web therebetween and an insulated sheath. This ligure-8 construction or any other insulated sheath conguration, permits the use of grounded metallic clamps to support the conductor bars in spaced relation to the desired support member. In other cases, it is preferable to use bare conductor bars, then the insulation must be provided in some manner. i

The present invention is a novel hanger clamp which will not only support a bare or insulated conductor bar but will do so irrespective of minor variations in its special relation to the support frame or wall.

The present invention includes a hanger adapted to be attached to a supporting frame or the like so that its horizontal orientation can be changed, a vise having insulated jaws pivotally mounted `in the bight of the hanger for restrictive rotational movement with respect thereto and means to close the vise so that the jaws grip the sheath of the conductor bar forming part of an overhead electrication system.

More particularly, the present invention comprises a U-shaped hanger, means to aix the hanger to a support member in a selected rotational orientation, a clamp to hold a conductor bar supported between the legs of the U-shaped hanger for rotational movement in the plane of the conductor bar and having inwardly projecting shoulders on edges interior of the hanger and outwardly aring other ends terminating in inwardly projecting tips so that, when clamp is closed, thetips are spaced apart a distance less than the thickness of the bare conductor bar to prevent the bar from being removed once Beyond these features, the vise part of the clamp is designed whereby the width of the jaws is substantially the same as the combined width of the legs of the hanger and the parts of the vise pivotally mounted therein so that a Iplurality of hanger clamps can be supported inside-by-side relation and yet take up minimum space transverse to the lay of the conductors.

Another novel feature resides in the construction of the jaws of the insulated vise that grip the conductor bar. They surround the conductor bar so that even if the insulation associated with the bar burns off or is otherwise destroyed, the clamp will still hold the conductor bar and prevent it from falling down.

Therefore, objects of the invention are to provide hanger clamps adaptable to a wide variety of applications, which are simple in construction and use `a minimum number of parts, and which are designed to prevent hot conductor bars from falling on plant personnel or equipment.

These and other objects, advantages, and features of the present invention may be more fully underst-ood when the following detailed description is read with reference to the drawings in which:

FIG. l is an enlarged perspective of the hanger clamp forming the present invention;

FIG. 2 is a side view of the hanger clamp;

FIG. 3 is a section taken along line 3-3 of FIG. 2; and

FIG. 4 is a section taken along line 4-4 of FIG. 3.

The hanger clamp includes a U-shaped hanger 11 having a vise or clamp member 12 pivotally supported by bolt 13 between its legs 15.

The hanger 11 is preferably formed of a resilient material such as steel or aluminum and the bight of the U has aperture 18 formed therein through which machine bolt 19` projects to support the hanger 11 on support member 20. Before the nut 21.is tightened, the hanger 11 can be rotated in a horizontal plane to place the jaws of the vise 12 in the plane in which the conductor bar is to be supported.

Once the hanger 11 is supported on the support member or frame 20, the vise 12, which includes a pair of mirror parts or jaw members 26, is pivotally supported interior of the legs of hanger 11 by machine screw 13.

The mirror parts 26 include inwardly projecting shoulders 31 at their upper ends (with respect to the top of FIG. 3), .apertures 32 to receive the supporting bolt 13 and skirts 33 formed on their lower ends. The latter have outwardly flaring portions which curvilinearly move to terminate in inwardly extending tips 35. The interior of the skirts 33 form the jaws or clamping portion 34 of the vise 12. In the exemplary embodiment, the entire vise 12 is formed of a heat resistant insulated material, such as a glass lilled polyester. A suitable one is No. 1404 manufactured by the Glastic Corp. of Cleveland, Ohio. By heat resistant is meant resistant to any temperature likely to be developed in the conductor bar due to current flow, including cases of severe overload.

As is particularly shown in FIG. 3, the diameter of the lobe of the illustrated insulated conductor bar 38 is greater than the distance between the tips 3S of the jaw members 26 when the vise 12 is closed. Even if the insulation 39 on the conductor bar 38 is destroyed, e.g., by excessive heat, the conductor 40 could not fall out of the jaws 34.

In order to place a conductor bar Iin vise 12, the machine screw 13 vis opened and the jaw members 26 are eXed outwardly against the resiliency of the legs of the U-shaped hanger 11 to permit the insertion of the upper part of the insulated conductor bar 38. Once the insulated bar 38 is inserted, nut 42 i-s tightened to maintain the vise 12 in its closed position. It will be noted that the inwardly projecting shoulders 31 of parts 26 contact each other to act as a fulcrum forl the closure of the jaws 34 and that the application of closing force by the bolt 13 is below the fu-lcrum point, intermediate the fulcrum and jaws 34. This positively biases the jaws 34 against the insulated conductor bar 38.

It will also be observed (FIG. 3) that the overall width of the skirt 33 and the insulated conductor 38 thereinis approximately the same as the combined width of the bolt 13 and nut 42, the supported part of the vise 12and the -legs of the U-shaped hanger 1,1. With this arrangement, a plurality of conductor bars can be disposed in side-by-side, closely-spacedrelation without any difficulty. Th-is is particularly desirable since, in most cases, a number of conductor bars must be provided to allow for the different power connections needed.

FIG. 2 illustrates how variations in the lay of a conductor bar 38 can be compensated for by rotating the insulated vise 12 Vabout the axis defined by boltv 13. FIG. 2 illustrates the hanger clamp and support member 20 when the conductor bar 38 (not shown) is to be supported parallel to the support member 20. The dotted line position of the support member and hanger clamp 11,' illustrates how variations in the orientation of conductor bar 38 with respect to the support member 20 can be accommodated by rotating the vise 12 with respect to the hanger 11. It will be observed that the angle between the lower edge or end of the hanger legs and a plane through the top part of the skirt 33 i-s designated 6. This marks the limitof the excursion or rotation of the vise 12 with respect to the hanger 11. Obviously, this can be varied to some extent by design or eliminated by rounding off the end of the legs of hanger 11, but here it provides a positive stop or limit to the degree of adjustability.

In use, a number of these hanger clamps 10 would be disposed along a supporting member 20 which might be the overhead frame of the building and an insulatedrconductor bar 38 supported by the clamps in more or less parallel relation to the support member. To clamp the conductor bar 38 in the jaws of the vise 12, the jaws 34 would be llexed outwardly against the resiliency o f the legs of the U-shaped hanger 11. The conductor bar,` 38 would then be placed interior of the jaws 34 and the nut 42 tightened on the boltl 13 to pivot jaws34 on the fulcrum dened by inwardly projecting shoulders 31. This would cause them to encompass and grip the upper part of the insulated conductor 38.

Any variations in parallelism of support member 20 and conductor bar 38 can be compensated for by pivoting the vise 12 with respect to the hanger clamp 11 as the conductor bar 38 is placed in the jaws 34 thereof.

While the invention has been described with respect to an exemplary embodiment, it should be apparent to those skilled in the art that certain variations are possible without departing from the spirit and scope of the invention. F or this reason, the invention should be limited only to the extent of the appended claims.

What is claimed is:

1. A clamp for supporting a conductor in spaced apart relation to a support member such as a frame, wall or the like comprising, in combination,

a support member;

a hanger attached to said support member;

a vi-se having insulated jaws pivotally mounted on said hanger;

a conductor bar having an insulated sheath; and

means cooperating with said hanger to close said vise so that said jaws are ilexed to grip the sheath of said conductor.

2. A clamp forv supporting a conductor in spaced apart relation to a support member such as a frame, wall or the like comprising, in combination,

a support member;

a U-shaped hanger depending from said support member; an insulated vise having a throat portion pivotally mounted in the bight of said U-shaped hanger and a pair of jaws which have inwardly extending tips; and

means to close said vise so that said jaws are flexed to grip a conductor;

said jaw tips extending partially around said conductor to prevent its removal until said vise is opened and said jaws are flexed outwardly.

3. A clamp for supporting a conductor in spaced apart relation to a support member such as a frame, wall or the like comprising, in combination,

a support member;

a U-shaped hanger extending from said support member;

an insulated vise having a throat portion pivotally mounted between the legs of said hanger and a pair of jaws with inwardly extending ends which support a conductor;

said pivotal mounting for said vise permitting it to to be rotated in the plane of said conductor;

said throat portion having inwardly extending parts which form a fulcrum a spaced-apart distance from said pivot point on the opposite side from said jaws; and means to close said vise whereby said jaws arel llexed to grip said conductor as they pivot about said fulcrum;

said jaw tips extending partially around said conductor to prevent its removal until said vise is opened and the jaws exed outwardly.

4. A clamp for supporting a conductor in a spaced apart relation to a support member such as a frame, wall or the like comprising, in combination,

a support member;

a U-shaped hanger attached to said support member;

so that said jaws are ilexed inwardly to grip the conductor and sheath;

said jaws constructed to encompass the insulated conductor to the'extent necessary to prevent the removal of the conductor until said jaws are opened.

5. A clamp for supporting a conductor in a spaced apart relation to a support member in accordance with claim 4 wherein the width of said jaws is approximately equal to the combined width of the hanger and mounting portion of the vise, said vise is rotatably supported between the legs of said hanger to permit the elevation of said jaws to be varied, and including means associated with said hanger and said vise'to limit the rotation of `said vise with respect to said hanger.

6. A clamp for supporting a length of conductor bar, which has a longitudinal axis, in spaced relation to a supporting frame, wall or ceiling comprising, in combination,

a U-shaped hanger having registering apertures formed through the legs thereof transverse to the longitudinal axis;

a threaded member aixed to the bight of said U- yshaped hanger and extending away from the legs of said hanger to support it in spaced relation;

a pair of mirror image insulated jaws having extended widths in planes parallel to said longitudinal axis;

each of said jaws having a flat body portion with a transverse aperture formed therethrough;

a shoulder projecting inwardly from one edge of said flat body portion a spaced apart distance from said apertures;

a skirt projecting downwardly and outwardly from the other edge of said body portion and having an inwardly curving configuration;

a threaded member disposed in said registering and transverse apertures to rotatably support said jaws in said hanger;

the clearance between the free ends of the legs of said hanger and said skirt permitting said jaws to pivot about said threaded member to vary the elevation of said conductor bar; and,

means to tighten said threaded member to cause the tips of the skirts formed on each of said jaws to pivot about the contacting inward shoulders of said jaws to exurally grip an insulated conductor bar therebetween;

said tips, after said threaded member is tightened, be-

ing separated by a distance less than the transverse width of said conductor bar supported therebetween to prevent said conductor bar from escaping said jaws even if the insulation is removed therefrom.

References Cited UNITED STATES PATENTS 6/ 1893 Englund 191-42 5/ 1899 Haskell 248-74 11/ 1903 Embley et al 191--40 12/ 1941 Steesen 248--62 8/ 1955 Denis 248-62 8/ 1964 Howell 191-23 X 5/1965 Litz 174-155 X FOREIGN PATENTS 3/ 1961 Canada. 11/ 1952 France. 6/ 1962 France. 11/ 1953 Germany.

ARTHUR L. LA POINT, Primary Examiner.

STANLEY T. KRAWCZEWICZ, Examiner. 

1. A CLAMP FOR SUPPORTING A CONDUCTOR IN SPACED APART RELATION TO A SUPPORT MEMBER SUCH AS A FRAME, WALL OR THE LIKE COMPRISING, IN COMBINATION, A SUPPORT MEMBER; A HANGER ATTACHED TO SAID SUPPORT MEMBER; A VISE HAVING INSULATED JAWS PIVOTALLY MOUNTED ON SAID HANGER; A CONDUCTOR BAR HAVING AN INSULATED SHEATH; AND MEANS COOPERATING WITH SAID HANGER TO CLOSE SAID VISE SO THAT SAID JAWS ARE FIXED TO GRIP THE SHEATH OF SAID CONDUCTOR. 